Uretroplastia com Retalho

Uretroplastia com Retalho
Ricardo Borges
Serviço de
Urologia CHL
(Diretor: Dr. J. Garcia)
U-score (urethral stricture score)
§ Reliable, validated grading scale
§ Describe the surgical complexity of anterior
urethral strictures
§ The stricture’s U-score correlates with
surgical time and complexity of procedure
required.
§ Valuable tool to grade anterior urethral
strictures and improve comparative
research
Eswara, Urology, 2015
Preoperative Assessment
Smith (1968): with normal bladder function, there will be no impact in flowrate until de
urethra diameter is <10 French
Important to have a clear anatomical assessment of the site and length of the stricture.
Combined ascending and descending urethrogram to image the urethra, supplemented
where necessary by urethroscopy
Non-obliterative
Obliterative
Preoperative Assessment
The length of urethral narrowing may not correspond directly to the length of ischemic spongiofibrosis
Turner Warwick, Urology, 1985
1. Intracorporal injection of
contrast
Chapple, BJU Int, 2004
Barbagli, Scand J Urol Nephrol, 1995
2. Ultrasonography
Beckert, J Urol, 1991
Davies, J Urol. 2009
Clinical role not established!
Recommendations
1. The first operation is likely to be the most successful, and preference should be given
to the simplest technique that is likely to be most effective, avoiding augmentation
urethral reconstruction if possible (Level 3; A).
2. If augmentation (substitution) urethral reconstruction is being considered, an onlay
flap for strictures in the penile urethra can also be considered (Level 3; B).
3. In most cases, grafts are preferred over flaps for augmentation urethral
reconstruction, particularly in the bulbar urethra, since there is a greater morbidity
with the use of flaps compared to with grafts, and they have similar efficacy (Level
2; B).
(…)
Urology, 2014
Flaps
vs.
Grafts
§ Time-consuming (and tedious) to harvest
§ Quick and relatively easier to harvest and deploy
§ Dissection is extensive
§ Inherently less reliable – in theory – because they have
to be revascularized
§ Scarring and loss of the normal contour of the penis
when its dartos layer has been redeployed from part
or all of its circumference
§ Similar restricture rate as flaps (15,5 e 14,5%
respectively)
McAnninch, W J Urol.1998
§ Positive indications in favor of a flap (all of which
interfere with the ability of a graft to take):
ü some instances of revision surgery;
ü any cause of local devascularization such as
radiotherapy (or severe peripheral vascular
disease);
ü local infection
§ Positive indications:
ü procedure of choice in augmentation when EPA is
not possible
ü Lichen Sclerosus
Recommendations
6. Tube substitution procedures should be avoided (Level 3-4; A).
7. Scrotal skin should be avoided where possible because of the high
associated morbidity (Level 3; A).
Urology, 2014
1. Principles of tissue transfer
A flap refers to tissue that is transferred with its native blood supply intact
Jordan, 1992
2. Blood supply to the urethra and Penile skin
Dual blood supply to the urethra
•
allows aggressive mobilization
of the spongiosum
Hypospadias (+ severe forms)
Prior urethroplasty
Distal blood supply
compromised
-> ischemic stenosis
3. Flap techniques
1. Penile skin flaps, are a reliable and time-tested tool for urethral
reconstruction
2. Use them correctly:
§
§
§
§
in the absence of prior flap surgery,
nonhirsute penile skin (foreskin and distal penile skin in particular)
reliable axial vascular supply
can be well mobilized and used to cover long urethral defects
3. Can be elevated from ventral or dorsal skin and taken in either the
longitudinal or transverse direction.
3. Flap techniques
1. Orandi (1968)
§ ventral, longitudinal flap
§ lateral pedicle
§ nonobliterative strictures within the penile
shaft that are not due to BXO
§ Success rate: 71.8%
Disadvantage:
proximal part of the pendulous or any part of
the bulbar urethra: hair-bearing skin is involved in
the reconstruction which can lead to recurrent
infections and stone formation.
Orandi, J Urol. 1972
K J Urol. 2013
Adv Urol. 2015
3. Flap techniques
For strictures isolated to the fossa navicularis…
2. Jordan (1987)
Blandy, Cohney, Brannen’s modification,
SeSy, Devine resurfacing
§ smaller, ventral penile skin flap that is rotated onto the incised urethral opening
§ Success rate: 100% (without LS). 50% (with LS)
a
b
c
Jordan, J Urol. 1987
Adv Urol. 2015
d
3. Flap techniques
For longer strictures…
3. Quartey / McAninch
§ both described methods of obtaining penile circular fasciocutaneous
island flap
§ versatile and hairless
§ can supply enough tissue to cover near panurethral defects.
§ minimal disfigurement of the penis (circumcision type incision)
§ Success rate: 85-90%
§ Modifications:
§ Morey - ventral midline extension (Q-flap).
§ El Dahshoury - zigzag-shaped annular penile fasciocutaneous flap
(modified McAninch flap)
Quartey, J Urol. 1985
McAninch, J Urol. 1993
Buckley, BJUI. 2007
3. Flap techniques
3. Flap techniques
SURGICAL TIPS – CRITICAL STEPS FOR
SUCCESS
1. Stretch penile skin during initial width
calibration for flap development, ideal
width 20–25 mm.
2. Elevation of buck’s fascia, support of
the tunica dartos superficial to the
neurovascular bundle.
3. Adequate mobilization of the skin and
pedicle flaps.
4. Epithelium to epithelium anastomosis,
water tight.
5. Complete stricture incision with
calibration.
SURGICAL PITFALLS
1. Fasciocutaneous flap redundancy –
diverticulum formation.
2. Skin necrosis – wrong dissection
plane.
3. Incomplete flap mobilization –
ventral bowing of the urethra.
4. Fistula formation – epithelial to
epithelial breakdown.
5. Recurrent stricture – inadequate
scar incision.
4. Selecting the right technique
§ Highly individualized
§ Dependent on multiple factors
§ Optimal repair will depend:
ü length and location of the stricture
ü presence or absence of healthy,
abundant penile skin
ü whether or not the corpus spongiosum is
intact.
§ Decision-making process quite complex;
§ Proper selection of tissue transfer technique
is paramount to success.
Turner Warwick, Urology, 1985
5. Approach to the appropriate selection of
grafts and flaps in urethral reconstruction
I. Glans and Fossa Navicularis
Wisenbaugh, Adv Urol. 2015
5. Approach to the appropriate selection of
grafts and flaps in urethral reconstruction
II.
Penile and Bulbar
Wisenbaugh, Adv Urol. 2015
5. Approach to the appropriate selection of
grafts and flaps in urethral reconstruction
III. Special Situations
Segment of obliterated or near-obliterated urethra
(not an adequate urethral plate to perform a ventral or dorsal
onlay graft):
1. Too long for an EPA or an Augmented anastomosis
2. Short, but at risk of urethral ischemia with urethral
transection (history of hypospadias or failed urethroplasty)
×
Tubularized grafts or flaps – high failure rate (58%)
ü Graft/Flap combination – success rate of 92% at 39 months
Wisenbaugh, Adv Urol. 2015
Morey, J Urol. 2001
Gelman, J Urol. 2011
5. Approach to the appropriate selection of
grafts and flaps in urethral reconstruction
Graft/Flap Combination
Wisenbaugh, Adv Urol. 2015
5. Approach to the appropriate selection of
grafts and flaps in urethral reconstruction
Graft/Flap Combination
Also useful in:
Panurethral strictures that are too long for repair with BMG even when
bilateral grafts are harvested.
… using as much BMG as possible in the proximal aspects of the stricture
… penile skin flap to repair the remainder of the stricture distally
Warner, Urology. 2015
Wisenbaugh, Adv Urol. 2015
Berglung, Urology. 2006
5. Approach to the appropriate selection of
grafts and flaps in urethral reconstruction
Graft/Flap Combination
Also useful in:
Long segment urethral strictures without a good graft bed (radiotherapy,
multiple previous urethral reconstructions).
… use of a well vascularized gracilis muscle flap (GMF) to support a ventral BMG
• 20 patients
• Success rate: 80% at 40 months
• Avoid urinary diversion/suprapubic tube
J Urol. 2014
6. Conclusions
§ Common language (U-score)
§ Adequate preoperative assessment
§ Yes…there is still a role for flaps in the BMG era
§ Criterious selection of technique and tissue transfer (Grafts vs. Flaps)